'Stalling' during DNA copying said possible source of diseases

YORK, England, April 18 (UPI) -- British researchers report they've found how breakdowns in the DNA copying process in cells can lead to mutations that contribute to cancer and other diseases.

Scientists at York University say they've discovered that the protein machines that copy DNA in a model organism pause frequently during this copying process, and that those pauses can create the potential for dangerous mutations to develop.

The researchers focused on a bacterium called Escherichia coli, a powerful model for studying the DNA copying process and many aspects of DNA metabolism in more complex organisms such as man.

"Our work demonstrates that when organisms try to copy their genetic material, the copying machines stall very frequently which is the first step in formation of mutations that, in man, can cause cancers and genetic disease," York biology Professor Peter McGlynn said.

"We have analyzed what causes most of these breakdowns and how, under normal circumstances, cells repair these broken copying machines," he said.

"Just as importantly, our work reveals that efficient repair of these breakdowns is very important to avoid corruption of the genetic code."

The research involved scientists at York, the School of Medical Sciences at the University of Aberdeen, the Center for Genetics and Genomics at the Queen's Medical Centre, University of Nottingham and the Memorial Sloan-Kettering Cancer Center, New York.